Modified cylindrical free drop container



March 3, 1964 J NOURSE ETAL 3,123,117

MODIFIED CYLINDRICAL FREE DROP CONTAINER Filed June 18, 1962 INVENTORS mlliam B Crawford .lss H No urse v ATTORNEY United States Patent 3,123,117 MODIFED CYLINDRICAL FREE DROP CGNTAINER Jess H. Nourse, Ypsilanti, Mich, and William B. Crawford, Mishawaka, Ind, assignors to the United States of America as represented by the Secretary of the Army Filed June 18, 1962, Ser. No. 203,415 Claims. (Cl. 150-1) The invention relates to free drop containers of the type which are adapted to contain commodities, usually liquids, and are dropped from aircraft without the benefit of parachutes for a free fall to the earth. Specifically, the invention is intended as an improvement over the devices disclosed in the US. Patents Nos. 2,700,517 to Stavely and 2,784,755, to Bender, particularly the latter.

Both of these prior art devices comprise hollow flat cylindrical bodies of flexible impervious material which include stabilizing means to insure that the containers land flat on the ground as that position has been found to be the one least likely to cause bursting of the container side wall area. Stavely stabilizes his device with an axially disposed streamer while Bender achieves stability by means of an annular fin concentrically disposed about the container. However, both prior art devices rely upon pure constructional strength to prevent bursting of the side walls upon impact. Thus, unless the container lands flat in every instance, which is difiicult to achieve, the force of the impact usually ruptures the side walls. Also, such side walls are sometimes ruptured by a flat landing on certain terrain, as rocks or concrete streets, hard ground, or the like.

With the foregoing in view, it is an object of the invention to provide an improved free drop container of the class described.

A further object is to provide such an improved container which includes novel means for cushioning or retarding resiliently the lateral expansion of the container which occurs upon impact.

A further object is to provide such an improved container wherein the cushioning means comprises a confined compressible gas or other media.

Other objects and advantages reside in the particular structure of the invention, the structure of the several elements thereof, combinations and subcombinations of such elements with each other and/ or the contents of the container, all of which will be readily apparent to those skilled in the art upon reference to the attached drawing which illustrates a specific embodiment of the invention and to the following specification wherein the invention is described and claimed.

In the drawing:

FIGURE 1 is a plan view of a container according to the invention;

FIGURE 2 is a vertical sectional view taken substantially on the plane of the line 2-2 of FIGURE 1 and showing the position of the parts and contents when the container is static and when it is falling free; and

FIGURE 3 is a fragmentary vertical sectional view like FIGURE 2 but showing the position of the parts and contents upon impact.

Referring specifically to the drawing wherein like reference characters designate like parts in all views, 10 designates generally a container according to the invention, which may include a top wall 11, an endless side wall 12 and a bottom wall 13. The top wall 11 may include a filling opening complete with a closure means 14 and adjacent handles for supporting the container 10 while it is being filled or emptied. Walls or wall portions 11, 12 and 13 are formed of any suitable flexible impervious material such as fabric material which has been impregnated, coated or both with rubber or rubber- 3,123,117 Patented Mar. 3, 1964 like plastic. It may comprise one or more plies and is substantially inelastic.

A cushioning chamber 16 of annular form surrounds the side wall portion 12 of the container 10 in concentric relation thereto. Chamber 16 comprises top and bottom wall portions 17 and 18 which may comprise the same material as the container proper and which include inner edge portions which are sealed to the container 10 proper or are even integral therewith in vertically spaced relation to each other. Walls 17 and 18 include outer edge portions 19 and 26 which are joined together in face-to-face relation to provide an annular stabilizing fin 21. The fin 21 may be pierced at intervals and reinforced to provide hand holds 22 for carrying the filled or empty container 10. Chamber 16 is gas tight and is normally filled with a compressible gas as air. However, it may conceivably be filled with other cushioning materials as solid foam rubber or a mixture of foam rubber fragments and air.

In use, the container 10 is substantially filled with contents, usually a liquid, and normally assumes the shape illustrated in full lines in FIGURE 2. However, when dropped from an aircraft, the center of gravity is lowered because of the stabilizing action of the tin 21 and the device assumes the shape illustrated in broken lines in FIGURE 2. Upon impact, however, the convex bottom of the container it? proper causes it to flatten out whereby the fluid contents are forced radially outwardly in all directions with considerable force. This causes the container to momentarily assume a doughnut like shape as illustrated in full lines in FIGURE 3. Thus, as the side wall 12 tends to flatten out from the broken line position, the walls 17 and 18 are diverged and the resilient contents of chamber 16 are compressed whereby to cushion the strain on the wall 12 and protect the same from rupture upon impact in a manner readily understood. This is true even when the Walls of the container 16 are formed of substantially inelastic material as laminations of fabric and an elastomer. Even such materials have a limited amount of stretch.

It is seen therefore, that the device of the invention is caused to fall in an upright manner by the fin 21 so that it lands on the bottom wall portion 13 which is convex while falling. By positioning an annular chamber filled with compressible material around the side wall portion 12, the container is reinforced in the area which is subjected to the greatest stress upon impact with the ground. The fin 21 although normal to the horizontal axis of the container when the latter is static, extends diagonally upwardly when the container is falling freely and the shape of the container itself is slightly modified to insure a low center of gravity. This arrangement has been found to be superior to other shapes which suggested themselves. It also caused the container to land right side up at all times when properly released from the aircraft. By extending the chamber 17 and 13 walls from the top and bottom of the side wall portion 12 and making such walls of equal width, the strain of impact is substantially equally distributed between chamber walls 17 and 18 and throughout the width of container side wall portion 12. Thus, a container remarkably free from rupture upon impact on all kinds of surfaces has been provided.

While there has been shown and described what is now thought to be a preferred species of the invention, it should be understood that the same is susceptible of still other forms and expressions. Consequently, the invention is not considered to be limited to the precise structure shown and described here nabove but only as hereinafter claimed.

We claim:

1. In a free drop fluid container, the combination with a container body of flat cylindrical form and a flexible annular fin surrounding said body, said body having an impervious side wall of flexible material; of an impervious annular chamber surrounding said body and forming a base for said fin, and said chamber being filled with compressible material to retard expansion of said side wall of said container upon impact of said container with the ground.

2. In a free drop fluid container, the combination with a container body of flat cylindrical form and a flexible annular fin surrounding said body, said body having an impervious side wall of flexible material; of an impervious annular chamber surrounding said body and forming a base for said fin, and said chamber being filled with a compressible gas to provide a resilient cushion operative to retard expansion of said side wall of said container upon impact of said container with the ground.

3. In a free drop fluid container, the combination with a container body of flat cylindrical form and a flexible annular fin surrounding said body, said body having an impervious side wall of flexible material; of an impervious annular chamber surrounding said body and forming a base for said fin, said chamber being formed by upper and lower walls of flexible impervious material, said upper and lower walls converging at said fin in radially outwardly spaced relation to said side wall to provide a cham her which is substantially triangular in cross section, and said chamber being filled with a compressible gas to provide a resilient cushion operative to retard expansion of said side wall of said container upon impact of said container with the ground.

4. In a free drop fluid container, the combination with a container body of flat cylindrical form and a flexible annular fin surrounding said body, said body having an impervious side wall of flexible material; of an impervious annular chamber surrounding said body and forming a base for said fin, said chamber being defined by two walls of flexible impervious material, said two walls having inner edges sealed to said chamber and outer edges sealed to said fin, and said chamber being filled with a compressible gas to provide a resilient cushion operative to retard expansion of said side wall of said container upon impact of said container with the ground.

5. In a free drop container, a hollow cylindrical container body having impervious walls including a flexible side wall, an impervious annular chamber surrounding said flexible side wall of said container and having impervious 45 flexible walls,-said chamber being filled with resiliently compressible material to retard expansion of said flexible side wall of said container upon impact of the same with the ground, and an annular fin secured to said chamber in outwardly spaced relation to said container.

6. In a free drop container, a hollow cylindrical container body having impervious walls including a flexible side wall, an impervious annular chamber surrounding said flexible side wall of said container and having impervious flexible walls, said chamber being filled with a compressible gas providing a resilient cushionoperative to retard expansion of said flexible side wall of said container upon impact of the same with the ground, and an annular fin secured to said chamber in outwardly spaced relation to said container.

7. In a free drop container, a hollow cylindrical container body havingimperviousv walls including a flexible side wall, an impervious annular chamber surrounding said flexible side wall of said container and having impervious flexible walls, said chamber being filled with a compressible gas providing a resilient cushion operative to retard expansion of said flexible side wall of said container upon impact of the same withthe ground, said chamber comprising upper and lower annular walls of flexible impervious material, said upper and lower walls having inner edges sealed to said side wall of said container in vertically spaced relation, and said upper and lower walls having outer edges sealed together in faceto-face relation radially outwardly of said container to provide a flexible annular fin.

8. A free drop container according to claim 7, wherein said upper and lower walls of said chamber are of substantially the same length in a radial direction.

9. A free drop container according to claim 8, wherein said inner edges of said upper and lower walls of said chamber are disposed in equispatial relation above and below the normal horizontal center of gravity of said container body.

10. A freerdrop container according to claim 9, wherein said fin is normally disposed in the plane of said center of gravity.

References Cited in the file of this patent UNITED STATES PATENTS 

1. IN A FREE DROP FLUID CONTAINER, THE COMBINATION WITH A CONTAINER BODY OF FLAT CYLINDRICAL FORM AND A FLEXIBLE ANNULAR FIN SURROUNDING SAID BODY, SAID BODY HAVING AN IMPERVIOUS SIDE WALL OF FLEXIBLE MATERIAL; OF AN IMPERVIOUS ANNULAR CHAMBER SURROUNDING SAID BODY AND FORMING A BASE FOR SAID FIN, AND SAID CHAMBER BEING FILLED WITH COMPRESSIBLE MATERIAL TO RETARD EXPANSION OF SAID SIDE WALL OF SAID CONTAINER UPON IMPACT OF SAID CONTAINER WITH THE GROUND. 